Electrode for rivet heaters



F. T. KITT ELECTRODE FOR RIVET HEATERS Filed March 6, 1920 M) lllllINVENTOR. .7 57 4 4 UNITED STATES PATENT O FRED '1. KITT, OF SEATTLE,

AMERICAN CAR AND F 01 NEW JERSEY.

WASHINGTON, I-KSSIGNOR, BY

FVFICE.

MESNE ASSIGNMENTS, TO

OITNDRY QUEER-ANY. OF NEW? BZ'OEK. N. A COHPGRATZON ELECTRODE FOR RIVEIHEATERS.

Application filed March 6, 1920. Serial No. 3

To all whom it may concern Be it known that I, F RED T. Kiri", a resident of Seattle, county of King, and State of IVaslnngton, have inventeda new and useful Improvement in Electrodes for Rivet Heaters, of whichthe follow complete description, reference the accompanying drawing, ofthis specification.

iiig is a full and being had to forming a part My invention relates toelectrodes or jaws similar for a rivet heater scribed in applicationSerial No.

filed by me on August 26th, being to provide means wh to the one de-319,983 1919, the object ereby rivets or the like may be convenientlyinserted in an electric circuit in such a manner that a large volume ofcurrent can be forced through them for the purpose of heating the same.

Another object is to provide means for cooling the points of contactwhich, in the ordinary process of heating by means of an electriccurrent, tends to overheat.

Fig. 1, indicates the secondary of a trans- 'in as shown former, whichterminates for holding rivets, a modification of enlarged view ofaddition of as the application of the these jaws.

Fig. 2 taken, partly in cross section, through the line a pair of jawsFig. 2 shows Fig. 3 is an 1, with the a rivet in order to show themethod of holding same in the jaws as well cooling means above referredto. Fig. 4 is a cross-section showing a detail the head of the rivet.

I have not considered it ne any other details of the tran one skilled inthe art will of the contact surface for cessary to show sformer, as anyunderstand the device from the drawing and this description.

In Fig. l, 1 indicates a sin per or other good conducting material,which terminates in aws 4 and 5, which latter are at an angle to eachother. The upper jaw 4 has a series of notches short sections parallelwith distances from the lower which form and at various aw 5. Thesenotches are for the purpose of accommodat ing rivets of differentlengths.

By inducing a heavy current in this closed circuit, composed of thecopper secondar y and the rivet,

as shown, the latter can be heated to melting point if desired.

In the modification shown in jaw is not iiotrhed movable block 3, anypoint on the jaw 4, in order to accommodate rivets oi different lengths.in enlarged view Fig. 3, 2 represents a flit with its head in contactwith block 3, and a. point with jaw 5. It is well known that when acurrent is passed through a series of conductors in simple mechanicalconnec tion with each other, the points of contact tend to heat fasterthan any other part of the circuit owing to the contact resistance,therefore, in heating rivets by the method described, the two ends willbecome heated much sooner than the body of the rivet. This is especiallytrue of the point as the head, being larger, radiates heat faster andthus keeps comparatively cool. To overcome the danger of overheating thepoint, I have made the lower jaw 5, with a depression for holding asmall quantity of tin, lead or the like where the point of the rivetmakes contact with the jaw. When the rivet becomes hot, this metalliquefies and forms a bath for the point of the rivet as indicated bythe dotted lines 8. This improves the contact and forms a radiator for acertain amount of heat all of which tends to keep the point fromburning. By this method it is possible to get the body of the rivethotter than the point which is a great advantage.

Fig. 4 represents a slight modification of the block 3, being a crosssection also through the line 1, Fig. 2. I show here an oval shapeddepression in the block designed to fit snugly the head of a rivet inorder to assure better contact and to hold the rivet more securely. Thisoval depression may be made either in the block 3, as indicated, or inthe faces of the notches in jaw 4, Fig. 1.

IVhile I have mentioned only the heating 1 1. tilt.

. +1 Lil of rivets in this specification, I believe the 9 which can befastened at the heating of rivets but to cover broaely the cooling ideadescribed.

Having described my invention, what 1 claim is, as follows: v

1. In an electric heater, the combination of means whereby current maybe passed through an element for the purpose of heating the same, andmeans for cooling a pointof contact with a bath of molten metal.

2. In an electric rivet heater, a secondary coil having angularly'disposed electrodes and a cooling bath of molten metal carried by one ofsaid electrodes.

3. In an electric rivet heater, a secondary coil having angularlydisposed. jaws provided with parallel rivet engaging surfaces one ofsaid surfaces being adjust-able to Vary the normal opening between saidsurfaces.

4:. In an electric rivet heater, a secondary coil having angularlydisposed jaws provided with parallel rivet engaging surfaces adapted toengage rivets at different distances from the apex of the angle made bysaid jaws.

5. In electrodes for an electric rivet heater, the combination of anupper and a lowerjaw extending at an angle to each other and a movableblock adapted to fasten to said upper jaw as shown and described.

6. In an electric rivet heater, a secondary coil having angularlydisposed jaws provided with parallel rivet engaging surfaces and meansto adjust one 01 said surfaces along its supporting jaw.

7. ln an electric rivet heater, a secondary coil having terminal jaws, arivet engaging surface movable along one of said jaws and a cooperatingrivet engaging surface carried by the other of said jaws.

8. In an electric rivet heater, a secondary coil having terminal jawsprovided with cooperating rivet engaging surfaces, one or said surfacesbeing shiftable along its supporting to vary the normal opening betweensaid surfaces.

FRED T. KITT.

lfVitnesses:

RAYMOND OGDEN, J OSEPH' OAKLAND.

